1. Field of the Invention
The present invention relates generally to a system for surface contaminant testing and more specifically to a system and method for testing a surface for at least one measurable property such as pH, the presence of chlorides or similar contaminants, or conductivity as a measure of the efficacy of a surface treatment applied to the surface.
2. Description of the Related Art
In commercial and industrial applications where the treatment of surfaces with protective coatings is required, it is often necessary to test the treated surfaces to determine whether the protective coating has been properly applied. Furthermore, prior to the treatment of, for example, steel surfaces, the surfaces must be thoroughly cleaned of contaminants and salts such as chloride salts so that corrosion doesn't occur under the treated or painted surface. Accordingly, there have been developed various and sundry prior art systems for determining the presence of contaminants of various types on surfaces.
As one example, salt contamination on steel surfaces is a widespread problem in the shipbuilding industry. Salt contamination is typically caused by the proximity of a steel ship to ocean air and water, as well as less obvious causes such as salt treatment of icy roads in proximity to the untreated material. Corrosion can occur quite rapidly after a surface is contaminated, so that surfaces must be cleaned, tested and treated quickly in order to avoid the deleterious effects which will eventually appear when a contaminated surface is treated or coated. Furthermore, painting over a salt contaminated surface will eventually cause failure in immersion service materials such as ballast tanks and the like. Ballast tank failures cause an enormous inconvenience and expense to repair since the ship must be removed from service to correct the problem.
Many prior art surface testing devices for various properties such as salinity, pH, or conductivity are typically complex and labor intensive systems that require a multiplicity of steps in order to accomplish the surface testing. In one popular example, a Bresle patch or sampler has been used as a means for measuring chloride contamination on treated surfaces. The Bresle patch comprises a latex membrane and a foam rubber gasket that creates a water tight sample extraction pocket in contact with a surface when a foam rubber gasket is secured to the surface via an adhesive. The watertight sample extraction pocket is then filled with distilled or deionized water, typically by use of a syringe. After agitating the water by rubbing the patch for a short time period, the water is removed, typically through a syringe or the like and analyzed by chemical reagents for a constituent property such as chloride ion content. The chemical analysis is typically done by using a “kit” supplied with reagents and instructions for use. The extracted water may also be analyzed for other properties such as pH, electrical conductivity, or the presence of chloride ions using conventional known-in-the art meters designed for those purposes. Of course, this method and system is quite complex and requires a great deal of labor and expertise to properly execute. Additionally, due to the complexity it is quite easy to make testing errors and obtain inaccurate data in such a prior art system.
Other methods of testing a surface for a constituent property are also known in the art but each of them also requires a large amount of time and energy to collect and analyze a single sample. In many prior art systems, various syringes, bottles of water and reagents, surface test patches and other equipment must be coordinated and assembled in an inhospitable industrial fabrication environment. These prior art methods are quite disadvantageous when testing large surface areas, since samples must be collected at many points around the area being treated in a short time before surface treatment can proceed.
Accordingly, there is a great need in the art for a system and method of testing for a constituent property on a surface that is both economical and capable of being conducted repeatedly and quickly by a user while yielding consistently accurate results.